Holddown device

ABSTRACT

A holddown device has an arm which is capable of being canted on a shaft to effect a friction lock between the two. The relationship between the shaft diameter and the diameter of a hole in the arm which receives the shaft is such that approximately a 3* to 5* angle is effected between the arm and the shaft when an article is being held by the device. A pad carried by the arm through a spring-biased pin engages an article being held. The compression spring urges the arm into its angular locking engagement with the shaft.

United States Patent lnventors Richard N. Reinhardt 621 W. Yale St.,Ontario, Calif. 91762;

Frank L. Ellings, 2074 White Bluff, San Dimas, Calif. 91773 Appl. No.797,653

Filed Feb. 7, 1969 Patented Apr. 20, 1971 HOLDDOWN DEVICE 4 Claims, 2Drawing Figs.

US. Cl 248/361, 248/ l 25 Int. Cl B65j 1/22 Field of Search 248/361,

361(B),125,124,122,410,154,(T.C.);211/84 [56] References Cited UNITEDSTATES PATENTS 936.767 10/ 1 909 Van Eyck 248/154X 1,785,746 12/1930Pilling 248/154 2,160,433 5/1939 Griffin... 248/147 2,891,753 6/1959Bittle 248/154X Primary ExaminerChancellor E. Harris Att0rneyChristie,Parker & Hale nowoovvn nisvrca BACKGROUND OF THE INVENTION The presentinvention relates to devices for holding objects in place and, more inparticular, to a friction-type holddown device which is particularlywell suited for holding various sized articles in place while they arebeing transported.

Meters for natural gas service are typically transported in pickuptrucks in specially designed racks. Typically, the racks have a railcircumscribing them to retain the meters in place. This guard or railnecessitates the lifting of the gas meters into and out of the racks.Moreover, meters are not held firmly in place and often bounce intransit.

Another problem attendant with the use of racks is that the racks do notlend themselves to use other than in the carriage of gas meters. Thus,when a service truck is called upon to transport articles other than gasmeters, the racks serve only as a hindrance.

In an effort to make access to the meters more convenient, a new type ofmeter rack has recently been introduced which accepts the meter in apivotable cradle. For transit, the cradle is pivoted into a stableposition interiorly of the sides of a truck with a guard or frame abouteach meter. When it is desired to remove the meter, the cradle is merelypivoted to an outboard position where meter access is possible. Whilemeter accessibility is well served by this rack, the rack is relativelyexpensive and does not accommodate itself to the problem of transportingthings other than gas meters. Moreover, the meter size accommodation ofthe improved rack is not as broad as would be desired.

Therefore, there is a present need for a holddown device SUMMARY OF THEINVENTION The present invention provides a holddown device which employsan arm which, when canted on a shaft, locks in place to hold an article.

In one form, the present invention contemplates that the arm have a holefor the arms receipt by the shaft. The relationship between the arm andshaft is such that canting of the arm produces seizure on the shaftalong opposite comers of the hole. A retaining member, preferably a pad,is used to engage the article being held. The retaining member is on apin and is force coupled to the arm through a compression spring. Thepin, in turn, is coupled to the arm, as in a hole in the arm, by akeeper.

In use, an upward reaction force from an article is exerted on theretaining member to compress the spring. The spring, in turn, exerts anupward force on the arm which cants the arm on the shaft to effect afriction lock between the arm and the shaft.

It has been found that the clearance between the hole in the arm and itscooperating shaft should be such that an inclination from the horizontalof the arm of about 3 to about 5 is possible, the inclination beingproduced by a holddown load transferred through the pad to the arm. Inother words, the angle between the shaft and the arm under load shouldbe from about 85 to about 87. If the amount of arm inclination possibleis less than this, the arm is too tight on the shaft and, as aconsequence, it is difficult to adjust the arm's height to accommodatedifferent sized articles to be held. Obviously, the greater the angle ofthe arm to the horizontal when holding down an article, the greater willbe the locking force. However, with large angles from the horizontal,the device is often difficult to use because the arm can interfere withan article. Large angles from the horizontal of the arm in its inuseposition also require an excessive hole diameter in the arm for theretaining member s pin to keep the retaining member level. The largehole diameter for the pin produces problems in keeper design to retainthe pin with the arm.

It is contemplated that a typical gas meter service truck will beequipped with an assembly having several of the holddown devices in arow. This assembly may be secured to the bed of the truck and adjacent,for example, a service box for tools and the like. When no meters are tobe transported, the arms can either be removed or swung inwardly againstthe service box allowing considerable room for transporting of articlesother than meters.

The present invention provides a very simple but highly reliableholddown device which may be used, for example, in service trucks fortransporting meters used in natural gas service. The holddown device isvery simple, lightweight, and effects a positive retention of articlesbeing held. Moreover, it does not occupy a large amount of space andtherefore, when it is not in use, there is ample room for transportingother articles.

These and other features, aspects and advantages of the presentinvention will become more apparent from the following description,appended claims and drawings.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is an elevational view, partlyin section, of a preferred form of the holddown device of the presentinvention as it would appear in use; and

FIG. 2 is a perspective view showing a typical bank of holddown devicesas they would be employed, for example, in a service truck.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A holddown device 10 accordingto the present invention is illustrated in FIG. I. Briefly, the holddowndevice includes a shaft I2, an arm 14 and a holddown pad assembly 16.

The arm is received on shaft 112 through a bore or a hole 18 in the arm.A clearance exists between the wall of the arm defining the bore and theshaft in order to permit the arm to be angularly displaced an amountequal to an angle a from the horizontal and to engage the shaft as isillustrated in FIG. 1, the displacement being in response to an upwardforce indicated by the arrow in this FIG.

It has been found that there must be sufficient angular displacement ofthe arm relative to the shaft to facilitate vertical position adjustmentof the arm. If the angle of inclination from the horizontal is toosmall, the arm tends to bind on the shaft. On the other hand, excessiveangular displacement from the horizontal makes it difficult to providean effective keeper for holddown pad assembly 16. A value of angle a offrom about 3 to about 5 has been found highly satisfactory in theresolution of these conflicting requirements by permitting armadjustment without binding on the shaft while permitting effectivekeeper design for holddown assembly 16.

In the holddown device of the present invention, the holddown padpreferably consists of a neoprene pad or disc 20 and a complementarycylindrical backing member 22 of, for example, steel. The pad should beof a resilient material to provide a firm gripping engagement with anarticle despite surface irregularities thereon. Moreover, a resilientpad of, say neoprene, provides a high coefiicient of friction forretaining an article against horizontal displacement forces.

A shaft or pin 24 is secured as by threads to the backing member. Thisshaft or pin is loosely received in a bore 26 of arm M. Bore 26 isoversized to allow pin 24 to parallel shaft 12 when arm I4 is canted.The possibility of this parallelism pennits pad or disc 20 to keep leveland in effective engagement with the flat top of an article, such as agas meter, being held. A keeper in the form of a lock ring 23 is securedin a groove in pin 24 and retains the pin with the arm. It is thiskeeper which necessitates an upper limit of angular displacement fromthe horizontal of arm 114. Bore 26 must progressively be increased indiameter relative to pin 24 with increasing angular displacement of arm14 from the horizontal if pad or disc 20 is to have the facility ofbeing level during holddown. With increased clearance between pin 24 andthe wall defining bore 26, there is an increased possibility of keeper28 pulling through the bore.

A compression spring 30 is provided for transmitting the force ofarticle engagement to the arm and from the arm to the shaft. The springconstant of spring 30 must be sufficient to keep the spring fromcompletely collapsing when engaging an article. This is necessary toaccommodate vertical displacement forces experienced while transportingmeters or the like with a truck over, say, a bump in the road whilemaintaining arm and shaft engagement.

Neoprene disc may be secured to backing member 22 by any suitablecommercially available cementing compound.

Shaft 12 is preferably of seamless tubing. The shaft may be secured to abaseplate 32 as by welding. This baseplate may, in turn, be secured tothe bed of the truck as is illustrated in FIG. 2.

For a series of holddown devices, a top brace 34 extending across thetops of the holddown devices is preferably provided. This top brace,which provides rigidity, may be in the form of a standard channel. Eachholddown device is coupled to the brace through a collar 36 secured asby welding to the web of the channel. Each collar is sized to receivewithin its bore an associated one of the shafts 12. A thumbscrew 38 maybe provided to secure the top brace to the end holddown devices in aseries of holddown devices. Preferably, if several of the holddowndevices are employed, additional thumbscrews may be provided at regularintervals along the length of the brace.

In use, an article, say a gas meter, is placed on the bed of the truckbeneath an arm 14 of one of the holddown devices. The arm is then raisedor lowered such that pad or disc 20 engages the top of the meter andspring 30 is compressed. This will cant arm 14 such that it firmlyengages shaft 12 to apply a substantial holddown force on the meter. Itshould be appreciated that the holddown force is equal to the springconstant of spring 30 multiplied by the displacement of the spring. ltshould also be appreciated that it is this force which must be balancedby the friction force produced by the engagement of the arm and theshaft at the inclined angle illustrated. When it is time to release theholddown device, spring 30 is further compressed and arm 14 is rotatedto free it from shaft 12. The arm may then be freely lifted upwardly tofree the article.

The holddown device of the present invention is marked in its simplicitywhile providing a reliable and easily used means for positivelyrestraining various articles. One of the desirable features of theholddown device is its ability to accommodate various sized articles bysimply positioning arm 14 on shaft 12.

We claim:

1. A holddown device for use in securing various sized articlescomprising:

a. a shaft;

b. an arm extending laterally of the shaft having a hole proximate afirst end thereof which receives the shaft, the hole having a diametersufficiently larger than the diameter of the shaft that the arm iscapable of seizing on the shaft along opposite comers of the wall of thehole when the arm is canted with respect to the shaft;

c. a pin received in the arm proximate the second end thereof fordisplacement generally parallel to the shaft;

(1. a keeper retaining the pin with the arm;

e. a retaining member secured to the pin for compressively engaging anarticle;

f. a compression spring disposed about the pin between the arm and theretaining member for transmitting a holding force to an article throughthe retaining member;

g. a baseplate secured to the shaft for the mounting of the device; and

h. a top brace rcmovably secured to the shaft at the top thereof forproviding rigidity.

2. The holddown device claimed in claim 1 wherein the diameter of thehole in the arm is sufiiciently larger than the diameter of the shaftthat the arm 15 capable of angular displacement from a position normalto the axis of the shaft of from about 3 to about 5.

3. The holddown device claimed in claim 2 wherein the retaining membercomprises a disclike pad of resilient material for engaging an articleand a rigid backing member secured to the pad, the pin being secured tothe backing member.

4. The holddown device claimed in claim 1 wherein the top brace is inthe form of a channel and a collar is provided for slipping over the topof the shaft and securing the top brace to the shaft, the collar beingaffixed to the interior side of the channel s web.

1. A holddown device for use in securing various sized articlescomprising: a. a shaft; b. an arm extending laterally of the shafthaving a hole Proximate a first end thereof which receives the shaft,the hole having a diameter sufficiently larger than the diameter of theshaft that the arm is capable of seizing on the shaft along oppositecorners of the wall of the hole when the arm is canted with respect tothe shaft; c. a pin received in the arm proximate the second end thereoffor displacement generally parallel to the shaft; d. a keeper retainingthe pin with the arm; e. a retaining member secured to the pin forcompressively engaging an article; f. a compression spring disposedabout the pin between the arm and the retaining member for transmittinga holding force to an article through the retaining member; g. abaseplate secured to the shaft for the mounting of the device; and h. atop brace removably secured to the shaft at the top thereof forproviding rigidity.
 2. The holddown device claimed in claim 1 whereinthe diameter of the hole in the arm is sufficiently larger than thediameter of the shaft that the arm is capable of angular displacementfrom a position normal to the axis of the shaft of from about 3* toabout 5*.
 3. The holddown device claimed in claim 2 wherein theretaining member comprises a disclike pad of resilient material forengaging an article and a rigid backing member secured to the pad, thepin being secured to the backing member.
 4. The holddown device claimedin claim 1 wherein the top brace is in the form of a channel and acollar is provided for slipping over the top of the shaft and securingthe top brace to the shaft, the collar being affixed to the interiorside of the channel''s web.